日本垃圾衍生燃料(RDF)的研究开发

综述垃圾衍生燃料（ Refuse Derived Fuel， R D F）的性能、研究开发概况，介绍了日本几个有代表性的垃圾衍生燃料生产利用设备

雾滴提升循环提升高度的分析与计算

前言雾滴提升循环（TheMistLiftCycle），一种利用海水温差进行发电的新技术方案，是美国能源研究与发展署（R＆D）的学者Ridgway在1977年率先提出来的。由于它是以...

现代雨水利用技术研究进展与研发重点

具有工程化、科技化、规模化内涵的现代雨水利用技术是现代节水农业技术的重要研究内容,已成为缓解干旱缺水,实现农业高效用水,降低常规农业用水量的有效措施。在分析现代雨水利用技术研究进展及其发展趋势基础上,指出现代雨水利用技术是传统雨水利用技术与新材料技术、现代生物技术、现代信息技术、现代灌溉工程技术等高新技术相结合的产物,具有多学科相互交叉、各单项技术相互渗透的明显特征。在此基础上,提出了近中期现代雨水利用技术研发的重点,即以重大前沿性技术研究为基础,研发与雨水利用相关的重要关键技术与产品,探索建立适宜的现代雨水高效利用技术体系。

稀土与过渡金属的萃取机理及分离方法的研究

随着化学工业的发展，稀溶液或难分离体系中有价物质的提取、富集成为化工分离学科中的重要研究课题之一。随着人们环保意识的增强，寻找新型、高效、清洁的工艺流程成为分离科学的热门话题。众所周知，在稀土矿中常含有许多过渡金属杂质，如锌、镉、铁、钻、镍等等，因此研究稀土与过渡金属离子的高效分离成为必然，这也是我研究工作的出发点。本论文主要包括以下几个方面的内容：1.研究了中空纤维膜器中HEH/EHP (P507)在盐酸介质中萃取分离衫、锌及锅的传质动力学，比较了聚偏氟乙烯膜和聚四氟乙烯和聚偏氟乙烯共聚物膜这两种膜材料的稳定性能，建立了界面反应动力学方程。考察了料液酸度、萃取剂浓度以及萃取剂不同氨化度对锌、福传质系数的影响。认为氨化p507不能提高锌、福的传质系数，却能提高稀土的传质系数，利用这一性质，就可能实现锌、镉与稀土离子的分离。这一研究为新型膜材料的应用提供了理论基石出。2．研究了中空纤维膜器中硫代有机磷酸萃取剂Cyanex302在硫酸介质中萃取分离锌、镉、铁、钻、镍和铺的传质动力学，探讨了各种因素对萃取速率的影响，获得了膜器中金属离子的传质模型及机理，同时采用膜器串联实现了锌、铺及锌、镉混合物的分离。3.研究了盐酸体系中伯胺1923与中性有机磷酸萃取剂Cyanex923和Cyanex925对ZnCl,和CdCl_2的协同萃取机理，用斜率法、等摩尔系列法确定了协萃配合物的组成并用皿谱加以证实。对于Zn的萃取，可能是由于空间位阻效应的影响，单一中性萃取剂对Zn2+的萃取有如下的关系：Cyanex923>Cyanex925，整个协萃反应的平衡常数是Cyanex923＞Cyanex925。然而，根据协萃系数R=D 最大/D_(中合)来判定协萃效应的大小，则有如下的关系：Cyanex923＜Cyanex925。这就说明了如果单一萃取剂的萃取越高，则协萃效应就越小。对于Cd的萃取，协同效应的大小为：Cyanex923＞Cyanex925。另外还求得了协萃反应平衡常数和协萃配合物生成反应平衡常数以及热力学函数值。且随温度增加，分配比减小，说明协萃体系为放热反应。对于同一协萃体系，不同金属离子的协萃效应的大小为Zn>Cd。这一研究为提高稀土与过渡金属离子的分离效率具有实际意义。4．研究了萃取剂的界面性质，考察了萃取剂伯胺N1923, Cyanex923、Cyanex925及Cyanex302单独存在以及混合存在时与不同水相（含金属离子的和不含金属离子的）的界面张力的变化情况，根据Gibbs等温吸附方程，得到了界面超量，求出萃取剂分子在界面上的表观横截面积A_i以及使界面达到饱和所需体相最低的萃取剂浓度（C_(min)）。结果表明伯胺盐的加入增加了Cyanex923呢Cyanex925的界面活性，提高了金属离子的分配效率。这对进一步研究其萃取动力学有指导意义。5.通过静态法研究了Cyanex302萃淋树脂在硫酸介质中吸萃Fe(III)、Zn(II)、Co(II)、Ni(II)的性能，考察了振荡时间、料液酸度、实验温度等条件对萃取性能的影响，结果发现CL－Cyanex302吸萃Fe(III)、Zn(II)、Co(u)、Ni(II)的能力有如下的顺序：Zn（II）>Fe（III）>>Co（II）>Ni（II）。Fe（III）、Co（II）、Ni（II)及Zn(II)的半萃pH值依次为1.6、3.8、5.9、1.3。这说明通过控制水相的酸度，就有可能实现这些金属离子间的分离，这对于分离具有实际的意义。

电荷在液/液界面上的转移反应

针对目前液/液界面电分析化学存在的问题,从三方面研究了电荷在液/液界面上的转移反应.主要结果如下：1将含有氧化还原电对的水相支撑在铂盘电极表面,倒置后插入到有机相中,与参比电极和对电子极构成常规的三电极系统,实现了液/液界面上的电荷转移反应.2应用电化学方法详细探讨了中性载体加速离子在微、纳米管支撑的微、纳米级-水/1,2-二氯乙烷界面上转移反应的机理、热力学和动力学.3研究了手性联萘冠醚与手性酪氨酸在微、纳米管支撑的微、纳米级-水/1,2-二氯乙烷界面上的选择性络合过程的势力学和动力学.研究结果表明R型冠醚易于与D-酪氨酸络合.

裂解型高聚物的共混辐射交联

本文对聚甲基丙烯酸甲酯（PMMA）和聚异丁烯（PIB）两种典型的辐射裂解型高聚物的共混体系聚甲基丙烯酸甲酯-聚氧化乙烯（PEO），聚甲基丙烯酸甲酯-聚偏氟乙烯（PVDF），和聚异丁烯-乙丙共聚物（EPR）进行了较为详细的研究，结果表明：1、PMMA-PVDF共混体系溶胶抽提发现，在此共混体系中，PMMA发生裂解，且随辐照剂量增加，体系可被抽出量增加，符合关系（D_o-D_R) = KR + b k，b是常数，R为剂量，D是归一后的PMMA的相对剩余量，PMMA在共混体系（PMMA-PVDF）中的辐射裂解遵守无规降解规则，适合1/((M-bar)_n) = K (R_o + R)关系。PMMA的裂解程度可直接由溶胶抽提决定。机械性能测定表明，PVDF的存在，对PMMA的机械性能的辐射损伤有保护作用，少量PVDF的加入，不影响材料的透明性，抗冲击强度大为增加，且经一定剂量辐照后，抗张强度和断裂伸长无显下降。结晶分析发现，PVDF不论在共混体系或均聚物中，经辐照到一定高的剂量，其DSC曲线上的结晶熔峰分裂为双重。和国外文献报道的结果正相反。由此得出PVDF中多种晶型的存在，及晶型在一定温度发生转化。2、PMMA-PEO共混体系 凝胶抽提，热形变测定，付立叶变换红外光谱和动态力学粘弹谱测定都证明，PMMA和PEO共混以后，无论是在真空，还是在空气中辐照，PMMA发生了交联。并且交联是在一定的PEO-PMMA混合配比和一定辐照剂量范围内进行的。在某一配比时，交联率达最高。用扫描电镜和透射电镜对共混体系的相结构形态进行研究表明。交联最好的组成比是在PMMA-PEO共混体系的相倒转点附近。溶液共混时，PMMA-PEO体系的互溶程度与共混的温度条件有关，温度高于PEO的熔点时，共混体系的互溶性要比常温时共混要好，这和理论预测的结果一致。红外分析的结果说明，PMMA的交联主要是通过残基结合的方式进行的。3、PIB-EPR共混体系 采用低温DSC对PIB-EPR共混体系的互溶性进行了研究，发现PIB-EPR的互溶性较好，其Tg转变为-拓宽的单峰。凝胶抽提指出，聚异丁烯经与乙丙共聚物共混以后，在一定配比和一定辐照剂量范围内，聚异丁烯发生了交联，且在一定配比时交联率达到最高。交联是否发生，还与共混的方式有关，溶液共混时不发生交联。低温DSC研究显示，溶液共混时，其互溶性不如机械共混时PIB与EPR的互溶性好，前者的Tg转变呈现出分裂的双峰。4、裂解型高聚物与交联型高聚物共混以后，是否可以发生交联，首要的是体系的互溶程度，体系越均匀，交联的可能性越大（但不是充分条件）。由于互溶性不好，PMMA和很多橡胶共混合不产生交联，PIB与1，2-PBD以及和其它一些不饱和橡胶共混合不产生交联。在PIB，1，2-PBD共混体系的DSC分析曲线上，Tg转变是两独立的双峰，对应于PIB和1，2-PBD的Tg转变。交联的可能性能否实现，还与交联聚合物的链结构，柔顺性，及两种分子链间的相互作用有关。PMMA与PEO和PVDF两者的共溶性都很好（分子水平上），但前者可交联，而同后者共混后则裂解。

BACKGATING AND LIGHT SENSITIVITY IN GAAS METAL-SEMICONDUCTOR FIELD-EFFECT TRANSISTORS

Three different types of GaAs metal-semiconductor field effect transistors (MESFET) by employing ion implantation, molecular beam epitaxy (MBE) and low-temperature MBE (LT MBE) techniques respectively were fabricated and studied in detail. The backgating (sidegating) measurement in the dark and in the light were carried out. For the LT MBE-GaAs buffered MESFETs, the output resistance R(d) and the peak transconductance g(m) were measured to be above 50 k Omega and 140 mS/mm, respectively, and the backgating and light sensitivity were eliminated. A theoretical model describing the light sensitivity in these kinds of devices is given. and good agreement with experimental data is reached.

Sensitivity of Total-Dose Radiation Hardness of SIMOX Buried Oxides to Doses of Nitrogen Implantation into Buried Oxides

In order to improve the total-dose radiation hardness of the buried oxides(BOX) in the structure of separa tion-by-implanted-oxygen(SIMOX) silicon-on-insulator(SOI), nitrogen ions are implanted into the buried oxides with two different doses,2 × 1015 and 3 × 1015 cm-2 , respectively. The experimental results show that the radiation hardness of the buried oxides is very sensitive to the doses of nitrogen implantation for a lower dose of irradiation with a Co-60 source. Despite the small difference between the doses of nitrogen implantation, the nitrogen-implanted 2 × 1015 cm-2 BOX has a much higher hardness than the control sample (i. e. the buried oxide without receiving nitrogen implantation) for a total-dose irradiation of 5 × 104rad(Si), whereas the nitrogen-implanted 3 × 1015 cm-2 BOX has a lower hardness than the control sample. However,this sensitivity of radiation hardness to the doses of nitrogen implantation reduces with the increasing total-dose of irradiation (from 5 × 104 to 5 × 105 rad (Si)). The radiation hardness of BOX is characterized by MOS high-frequency (HF) capacitance-voltage (C-V) technique after the top silicon layers are removed. In addition, the abnormal HF C-V curve of the metal-silicon-BOX-silicon(MSOS) structure is observed and explained.

Design and numerical analysis for low birefringence silica on silicon waveguides

A new fabrication technology for three-dimensionally buried silica on silicon optical waveguide based on deep etching and thermal oxidation is presented. Using this method, a silicon layer is left at the side of waveguide. The stress distribution and effective refractive index are calculated by using finite element method and finite different beam propagation method, respectively. The results indicate that the stress of silica on silicon optical waveguide fabricated by this method can be matched in parallel and vertical directions and stress birefringence can be effectively reduced due to the side-silicon layer.

Polarization-Insensitive Silica on Silicon Arrayed Waveguide Grating Design

A new technology for fabrication of silica on silicon arrayed waveguide grating (AWG) based on deep etching and thermal oxidation is presented.Using this method,a silicon layer is remained at the side of waveguide.The stress distribution and effective refractive index of waveguide fabricated by this approach are calculated using finite element and finite difference beam propagation method,respectively.The results of these studies indicate that the stress of silica on silicon optical waveguide can be matched in parallel and vertical direction and AWG polarization dependent wavelength (PDλ) can be reduced effectively due to side-silicon layer.

High-speed electrooptical VOA integrated in silicon-on-insulator

In this paper, we present simulation results of an electrooptical variable optical attenuator (VOA) inte-grated in silicon-on-insulator waveguide. The device is functionally based on free carriers absorption toachieve attenuation. Beam propagation method (BPM) and two-dimensional semiconductor device simu-lation tool PISCES-Ⅱ were used to analyze the dc and transient characteristics of the device. The devicehas a response time (including rise time and fall time) less than 200 ns, much faster than the thermoopticand micro-electromechanical systems (MEMSs) based VOAs.

Characteristics of AlGaN/GaN HEMTs Grown by Plasma-Assisted Molecular Beam Epitaxy

AlGaN/GaN high electron mobility transistor (HEMT) materials are grown by RF plasma-assisted molecular beam epitaxy (RF-MBE) and HEMT devices are fabricated and characterized. The HEMT materials have a mobility of 1035cm~2/(V ? s) at sheet electron concentration of 1.0 * 10~(13)cm~(-2) at room temperature. For the de-vices fabricated using the malt-rials,a maximum saturation drain-current density of 925mA/mm and a peak extrinsic iransecmductance of IHfimS/mm are obtained on devices with gate length and width of l/-im and 80/im respectively. The f_t, unit-current-gain frequency of the devices,is about 18. 8GHz.

Design and Fabrication of Ultracompact 3-dB MMI Coupler in Silicon-on-Insulator

An ultracompact 3-dB coupler is designed and fabricated in silicon-on-insulator,based on 12 line tapered multimode interference(MMI) coupler.Comparing with the conventional straigth MMI coupler,the device is-40% shorter in length.The device exhibits uniformity of 1.3dB and excess loss of 2.5dB

Stress analysis of silica-based arrayed waveguide grating by a finite element method

The stress distribution in silica optical waveguides on silicon is calculated by using finite element method (FEM). The waveguides are mainly subjected to compressive stress along the x direction and the z direction, and it is accumulated near the interfaces between the core and cladding layers. The shift of central wavelength of silica arrayed waveguide grating (AWG) on silicon-substrate with the designed wavelength and the polarization dependence are caused by the stress in the silica waveguides.

Effect of rapid thermal annealing on the Raman spectrum of Si0.33Ge0.67/Si (100) alloy

The effect of thermal annealing on the Raman spectrum of Si0.33Ge0.67 alloy grown on Si (100) by molecular beam epitaxy is investigated in the temperature range of 550-800 degrees C. For annealing below 700 degrees C, interdiffusion at the interface is negligible and the residual strain plays the dominant role in the Raman shift. The strain-shift coefficients for Si-Ge and Ge-Ge phonon modes are determined to be 915 +/- 215 cm(-1) and 732 +/- 117 cm(-1), respectively. For higher temperature annealing, interdiffusion is significant and strongly affects the Raman shift and the spectral shape.